The proposed research is aimed at elucidating various conformational and metabolic aspects of the pituitary hormones, lutropin, somatotropin, and corticotropin. Also, studies are in progress on the isolation and characterization of mitogenic factors and of a renotropin. Conformational studies involve circular dichroism, ultracentrifugation, and electron-spin-resonance; metabolic studies include quantitation and explanation of the rapid plasma clearance of hormones and clarification of the nature of biotransformations of circulating hormones. Urinary gonadotropins (from both pregnancy and non-pregnancy urine) are being investigated and compared with the tissue components. Lastly, limited conformational studies will be conducted on interesting non-pituitary hormones and factors such as insulin, somatostatin, and peptide opiates.